The present invention relates to an apparatus for fabricating a semiconductor device and a method thereof and more particularly, to an apparatus for drying a semiconductor wafer using the Marangoni effect and a method thereof.
A process step for fabricating an integrated circuit on a semiconductor wafer requires cleaning the semiconductor wafer to remove residual chemicals, small particles, and contaminants generated during various fabricating processes. In particular, when a highly integrated circuit is fabricated, special attention is paid to the process of cleaning minute contaminants attached to the surface of the semiconductor wafer.
The process of cleaning the semiconductor wafer is divided into a chemical solution processing process (a liquid chemical processing process) for etching or separating the contaminants on the semiconductor wafer by chemical reaction, a rinsing process for rinsing the liquid chemical processed semiconductor wafer by pure water, and a drying process of drying the rinsed semiconductor wafer.
At an initial stage of semiconductor fabrication, a spin dryer using centrifugal force was used as a single wafer type dryer for the drying process. An example of the spin dryer is disclosed in U.S. Pat. No. 5,829,256. However, as the integrated circuit becomes increasingly complicated, it is difficult to completely remove minute water drops that remain on a wafer resulting from the centrifugal force of the spin dryer because a large number of water marks is generated on the wafer after the drying process.
To prevent water marks from generating on a wafer, a Marangoni dryer has recently been used. An example of the Marangoni dryer is disclosed in Japanese Patent Laid-Open Publication No. 10-335299. The Marangoni dryer is a device for performing the drying process using the Marangoni effect after accommodating wafers in a processing tub. Therefore, when the drying process is performed on a group of wafers, contaminants reside in the processing tub. But, the contaminants may contaminate a subsequent group of wafers on which the drying process is performed in the processing tub. In particular, when the entire liquid chemical processing process, rinsing process, and drying process are performed in one processing tub, the above-described problem becomes more severe.